Cylinder for internal-combustion engines



CYLINDER FOR INTERNAL-COMBUSTION ENGINES March 15, 1949. H. R. RICARDO Filed June 10, 1946 7 Sheets-Sheet 1 fzsoenlor A Norm March 15, 1949. H. R. RICARDO CYLINDER FOR INTERNAL-COMBUSTION ENGINES Filed June 10, 1946 7 Sheets-Sheet 2 lh lll n l I nuentor March 151949. I I I H. R. RICARDO I 2,464,462 7 Filed June 10, 1946' CYLINDER FOR INTERNAL-COMBUSTION ENGINES 7 Sheets-Sheet 5 FIGS.

l i J a G H a 4 A F 1 or 2 3 K\ *"K Inventor.

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A tlorney March 15, 1949.

'H. R. RICARDO CYLINDER FOR INTERNAL-COMBUSTION ENGINES 7 Sheets-Sheet 4 Filed June 10, 1946 I nlor \\\\\\\\\\\\\l we March 15, 1949. 14, RIQARDQ 1 2,464,462

CYLINDER FOR INTERNAL-COIBUSTION ENGINES Filed June 10. 1946 7 Sheets-Sheet 5 In uenlor A Home y March 15, 1949. H, RlCARDo 2,464,462

CYLINDER FOR INTERNAL-COMBUSTION ENGINES Filed June 10, 1946 v 7 Sheets-Sheet 6 Altorngy Patented Mar. 15, 1949 ERNAL-COMBUSTION ENGINES l Barry Ralph Ricardo, London, England Application June 10, 1946, Serial No. 675,757 In Great Britain October 10, 1945 2 Claims. (01. 123-173) CYLINDER FOR INT 1 This invention relates to cylinders for internal combustion engines and has for its object to provide a construction more particularly, but not exclusively, adapted for multlcylinder engines in i which the cooling of the cylinder barrel, more especially in the neighbourhood of the head; will be improved and the casting of the cylinder block simplified, while in the case of a multicylinder engine the centres of the cylinders can be kept as close as practicable.

In known constructions of cylinder in which the head is detachable the fact that the top of the cylinder and the bottom of the head constitute' layers or decks at the zone of maximum heat flow is an undesirable feature. The number and size of the bolts and'bosses required to ensure a gas-tight joint between the head and the cylinder is such as to interfere seriously with both the water circulation and the arrangement of the valve ports and passages. The gasket joint itself is a weakness and source of trouble. On the other hand there are also objectionable. features present invention avoids the above objectionable features and moreover has several advantages.

According to this invention the improved cylinder construction comprises in combination a cylinder block with the cylinder head preferably formed integral with the barrel or jacket, a wet liner held in the cylinder block so that the end of the liner with interposed packing butts up against the face of the cylinder head, with an in known constructions of cylinder in which the 4 headand barrel are formed integral. In the first place the valves are less readily accessible than in a construction in which the head is detachable and the crank case and cylinder block cannot be formed as an integralcasting and consequently some sacrifice in stiffness is involved. It would seem that no really satisfactory form of renewable liner is at present available. for use with a cylinder having the head and barrel integral. Then the casting of the cylinder block is complicated by the double walling of the cylinder barrel. There are difliculties associated with and" objectionable features in the connection between the cylinder block and the crank case and in the formation of these parts to provide for this connection. For example the bolt bosses which hold the cylinder block to the crank case must be kept shallow enough to lie under the end of the water jacket, or alternativelythey must be spaced a long way out from the cylinder barrel, either arrangement being objectionable. In order to provide sufficient depth of crank case the cylinder holding downflange must be above the bottom of the cylinder block and consequently the barrels of the cylinders must be extended below the flange and this involves difficult and expensive machining of the face of the flange. The necessity for a water space between adjacent cylinder barrels prevents the centres of the cylinders being brought as close together as isdesirable.

A construction of cylinder according to the interposed packing, and 2.- gland-like ring by which the liner is held in the cylinder block this ring engaging an annular shoulder on the exterior of the liner and being connected by studs to the adjacent end ofthe :ylinder block.

The water space between the liner and the cylinder block or jacket is formed as a passage which runs around and along the liner between it and the cylinder barrel, and there is a gallery for distributingwater in the cylinder block at a place intermediate in the length-of the liner with a communication between this gallery and one end of the passage around the liner. A communicating passage is provided adjacent to the cylinder head between the other end of this surrounding water passage and the water space in the cylinder head. The water space around the liner may be a spiral passage or otherwise formed as described hereunder.

If the passage around and along the liner has wholly or partly a spiral form it is constituted by a spiral rib formed on the exterior of the liner and having a uniform radial depth so that when the-liner is in position this rib lies throughout its length close to the surface of the cylinder jacket. In some cases it may be desirable to form the spiral water passage by passing a spring-like spiral coil of wire or rod of suitable section over the outside of the liner. Preferably this spiral would be of square section and would not be of spring material. This spiral member need not be a close fit either on the surface of the liner or against the inner surface of the cylinder block and it can be of such length that a complete annulus is provided at the levels of the water inlet and outlet. The spiral member may be secured for example at one end only either to the liner or to the cylinder block by such suitable means as may be convenient.

In-an alternative form the passage around and along the liner may be constituted by a series of spaced annular ribs on the exterior of the liner, each rib being cut away at at least-one point in the circumference of the liner so that the coolant after flowing around the liner in a space between two ribs can flow through the gap in the one rib into the next adjacent annular space. In this second annular space the coolant must flow around the liner to its opposite side and through the gap in the next annular rib. These gaps in adjacent ribs are in diametrically opposite positions so that the coolant flowing over the length of the exterior of the liner will follow a zigzag course passing in succession through the several spaces or grooves between the annular ribs.

The spiral water passage or the alternating ribs and grooves need be arranged in only a part of the water space, for example in about that one-third of the total length of that space which surrounds the end portion of the liner nearest to the cylinder head. Thus circumferential flow of the current will take place especially around the part of the liner where there is the greatest heat flow.

In one construction of cylinder ports for inlet and exhaust valves are formed in the head of the cylinder and the passage through which the water from the adjacent end of the spiral passage around the liner flows to the water space in the cylinder head is formed and arranged so that the stream of water issuing therefrom will be directed across the cylinder head between the parts enclosing these ports and the passages thereto. The passage through which the water flows from the inner and cylinder head end of the spiral passage around the liner into the water space in the head of the cylinder may be constituted by a chamber at the side of the head which is closed in by a cover plate with a tubular connection between the end of the spiral passage and this chamber and another tubular connection between this chamber and the water space in the head of the cylinder.

Ina construction of the improved cylinder adapted for an engine operating on the twostroke cycle with one or more valve-controlled exhaust ports in the head of the cylinder and scavenging air inlet ports in the wall of the liner controlled by the piston and located within an air belt formed in the cylinder block, a water passage is provided adjacent to this air belt and between it and the head of the cylinder and communicating with one end of the spiral passage around the liner, while the passage through which the water flows from this spiral passage into the water space in the head of the cylinder is formed and arranged so that the water stream is directed on to the casing enclosing each exhaust port and the passage therefrom.

A construction of cylinder in which the features described above are embodied has the following advantages. able wet liner. The cylinder casting is simplified and the cored water space does not extend appreciably below the head. The bolt bosses at the base of the cylinder block can be of ample depth and closely. adjacent to the actual cylinder jacket or barrel so that there is no division of responsibility in the structure as there is between the cylinder barrel and jacket in a conventional integral cast construction. The liner can project below the cylinder flange without difiiculty and the cylinder block can be kept short thereby permitting a deep and still crank case to be used while at the same time the operation of machining the lower flange of the cylinder block is made easy. The distance between the cylinder centres can be reduced to the absolute minimum. A high velocity water circulation is provided right up to the top of the liner. Though the liner is in should be needed to make a joint with the en- It provides a readily detachclosed packing washer at the top of th liner and the size of the studs which hold the gland ring and secure the liner need be suflicient only to withstand gas pressure on the top end of the liner in the event of complete failure of the joint made there by the washer. The rubber or like sealing rings around the lower end of the liner can be entered easily and are visible during their entry. The construction permits the flow of coolant between the valves to be concentrated in a simple manner.

The accompanying drawings illustrate by way of example how the invention may be applied in practice to the construction of the cylinders for engines operating on the four-stroke and twostroke cycles. In these drawings,

Figure 1 is a longitudinal sectional elevation of one cylinder for an engine operating on the fourstroke cycle.

Figure 2 is a view in plan of the outer end of the cylinder shown in Figure 1.

Figure 3 is a vertical sectional elevation of two of the cylinders in a cylinder block for an engine operating on the four-stroke cycle.

Figure 41s a transverse section on the line 4-4 in Figure 3.

Figure 5 is a longitudinal sectional elevation of one cylinder for an engine operating on the two-stroke cycle.

Figure 6 is a vertical section on the line 6-6 in Figure 5 showing two of the cylinders in a block.

Figure '7 is a transverse section on the broken line 1-1 in Figure 6 showing sections in two different planes normal to the axes of the two cylinders.

Figure 8 is a sectional elevation similar to Figure 1 but illustrating an alternative way of forming the spiral water passage around the liner.

Figure 9 is a. longitudinal section similar to Fig ure 1 but in which the liner is shown partly in elevation, this figure illustrating an alternative formation for the passage for the coolant around and along over the outer surface of the liner.

Figure 10 is a section on the line l0l0 in Figure 9 looking in the direction of the arrows.

Figure 11 is a longitudinal sectional elevation similar to Figure 1 but showing the application of the invention to a construction of cylinder in which the head of the cylinder is detachable. This View also shows a modification in the arrangement of the spiral water passage around the liner.

Referring to the construction shown in Figures 1 to 4 which as mentioned illustrate the invention as applied to a cylinder block for an engine operating on the four-stroke cycle, the cylinder block A is made of cast iron or a light alloy and has east along the lower part of the block a passage or gallery B for the distribution of water to the several cylinders. In this case the head of the cylinder A is shown as integral with the barrel A and the upper part of the cylinder block is formed with a water jacket C. cast integral with the block. Within the water space thus formed are inlet and exhaust passages D and E of suitable shape and leading from ports in the cylinder head these ports being controlled by poppet valves in a normal manner. Within the cylinder block A is a liner F formed. externally with a spiral rib G which when the liner is in place in the cylinder block lies throughout its length close to but preferably not touching the inner surface of the cylinder barrel thus forming a spiral water passage H throughwhich the coolant will flow space C in the cylinder head conveniently comprises a chamber J of suitable dimensions formed preferably so arranged the at the side of the head and closed in by a cover plate J Tubes J and J 'lead respectively from the upper end of the spiral water space H into lateral chamber J and from this chamber The tubular passage J is that a stream or water at high velocity will be directed from it between the inlet and exhaust valves and the passages D and E leading to these valves as may be seen in Figure 3.

The liner F is held in place in the cylinder block A by a ring K resembling a gland and comprising a cylindrical portion with an outwardly directed flange K at its outer end. The inner end of the cylindrical part bears against an annular shoulder F formed on the exterior of the liner F while the ring K is drawn up to the cylinder block A by studs K passed through the flange K By this means the-inner end of the liner F is forced against a packing ring L which lies on the face of the cylinder head A or in an annular recess formed therein. On the outside of the liner F and near the shoulder F against which bears the end of the gland ring K there are annular ribs F which provide between them and the rib or shoulder F grooves, preferably two in number as shown in Figure 1, in which are packing rings M of rubber or other suitable material. Conveniently a passage N running radially outwards through the block A leads from an annular space between the grooves formed for example in one of the annular ribs F and serves to carry all any water which may leak down to the packing rings.

It is desirable to relieve the inner edge of the cylindrical part of the gland ring K at places such as K near the holding studs K thereby ensuring a more even distribution of the axial thrust around the ring. These studs K are not called upon to withstand gas pressure so long as the joint between the inner end of the liner to the water space C.

F and the end of the cylinder A functions properly because gas pressure cannot reach and act on the end of-the liner while the joint at, L remains tight.

Referring now to the construction shown in Figures 5, 6 and '7 which illustrate the application of the invention to a cylinder block for an engine operating on the two-stroke cycle, as can be seen, the main features described above remain the-same but the water distributing passage or gallery B in this case is placed in-the cylinder block A ports F in the wall of the liner F. The spiral passage H around the liner runs from the gallery B with which it is in communication through the passage 28 and between the part below the gallery B and the adjacent side of the air belt a seal is formed by a shoulder F on the exterior of the liner and the adjacent part of the cylinder block with an interposed washer P of cork or other material. Below the air belt 0 the seal is provided by a piston ring or other suitable packing P in a groove formed between annular ribs F F on the liner one of these ribs F being that against which bears the rin K which holds the liner in position.

above the scavenge air inlet In the cylinder head A are exhaust ports E controlled by poppet valves and on to the parts around these valves is directed the high velocity stream of water coming through the tubular passage J into the water space 0 in the cylinder head, The arrangement here for the flow of coolant is as already described, namely with a tubular passage J through which the coolant flows fromthe upper end of the annular spiral passage H into the lateral chamber J from which leads the tubular passage J As in the previously described construction, the liner is held in place by the gland ring K and studs passing through the flange K at'the outer end of this ring into the adjacent part of the cylinder block A.

Referring to the modification shown in Figure 8 which again illustrates a cylinder for an engine operating on the four-stroke cycle, here the spiral water passage H between the liner F and the wall of the cylinder block A is formed by a coil of wire or rod G of square section which is passed over the liner F and lies between it and the adjacent wall of the cylinder block A.

I The upper end of this coil G bears against the head A of the cylinder and at its lower end bears against the annular rib F on the liner. In other adjacent rib L respects the arrangement here shown is as described above with reference, to Figure 1.

Referring to the modification shown in Figures 9 and 10 where the arrangement is illustrated as applied to a cylinder construction for an engine operating on the two-stroke cycle, in place of the water passage around and along the liner being spiral it is here constituted by a series of separate spaces or grooves H running round the outside of the liner F, these spaces being formed between annular ribs L, L L etc, with a gap in the continuity of each rib. These gaps are diametrically opposite with respect to the liner so that the'gap L in one rib L lies on the opposite side of the liner to the gap L in the next Thus the coolant will flow from the gallery B through the passage B into the first of the annular spaces H and having passed and onwards through the staggered gaps in the other annular ribs to the head M of the liner,

, whence the coolant will now through the radial passage J into the lateral chamber J and so into the water space in the cylinder head A Apart from this formation of the water passage around the liner the construction and arrangement is similar to that described above with reference to Figures 5 and 6.

Referring to Figure 11 this shows a construction of the cylinder A with a detachable head A In this case at the inner end of the cylinder there is formed within it a shoulder A on which lies the packing ring L and against which the end of the liner F butts up when the gland ring K, K is tightened up. In this case the spiral passage around the liner and between it and length of the liner it is provided externally with a spiral rib G which forms the spiral Water passage H along which the water is compelled to flow around that end portion of the liner F which is subjected to the greatest heat fiow. From the end of this spiral passage H the water passes out through the passage J into the lateral chamber J and thence through the tubular passage J into the water space E in the detachable head A.

The constructions described above enable the cylinder block castings to be much simplified and the centre-to-centre distance between the cylinder axes can be reduced to as small a value as practical. The arrangement also enables a high velocity water circulation to-be maintained around the cylinder barrels and across the valves and greatly facilitates the removal and insertion of liners.

Reduction of the distance between the centres of the cylinders and heat transference both require a thin liner which can be used in the present construction.

Strain distortion and cyclic variations in such distortion depend largely on the maximum axial force applied to the liner and the cyclic variation in strain imposed upon it by the periodic rise and fall of the cylinder head due to the gas pressure cycle. In certain known'constructions of integral cylinder employing long holding-down bolts and thin liners, which are necessarily under the full compression of the holding-down bolts, both maximum force and cyclic strain are very large. In the present construction the main gas forces directly affect only the relatively massive outer member, i. e. the cylinder block, where the crosssection may be made large, thereby reducing the variation in axial strain to a minimum amount. The initial force on the thin liner in. the present construction is therefore reduced to the amount required to make a joint on the narrow enclosed joint ring at the head of the cylinder, while the strain cycle is also reduced to the small variation in length of the massive cylinder casting.

What I claim-as my invention and desire to secure by Letters Patent is:

1. A multi-cylinde-r construction for an internal combustion engine having in combination a cylinder block comprising a barrel and a head, a wet liner inserted in the barrel so that the inner end of the liner with interposed packing butts up against the face of the cylinder head, a passage for coolant around and along the liner and between it and the cylinder barrel, a gallery constituting a passage for coolant running along in the outer part of the cylinder block with a communicating passage between this gallery and one end of the said passage for coolant around and along the exterior of each liner, and a chamber at one side of the cylinder head which is closed in by a cover plate with a connection between the adjacent end of the said passage around the liner and this exterior chamber, and another connection between this chamber and the space for coolant in the head of the cylinder, an annular shoulder on the exterior of the liner towards its outer end. a gland-like ring passed over the outer end of the liner so that the end of this ring lies against the said annular shoulder on the liner, and studs passing through the gland ring into the adjacent part of the cylinder block and serving through the ring to hold the liner in place.

2. A multi-cylinder construction for an internal combustion engine having in combination a cylinder block comprising a barrel and a head, a Wet liner inserted in the barrel so that the inner end of the liner with interposed packing butts up against the face of the cylinder head, a separately formed spring-like coil placed on the exterior of the liner and forming when the liner is in position a spiral passage for coolant around and along the liner and between it and the cylinder barrel, a gallery constituting a passage for coolant running along in the outer part of the cylinder block with a communicating passage between this gallery and one end of the said passage for coolant around and along the exterior of each liner, and a chamber at one side of the cylinder head which is closed in by a cover plate with a connection between the adjacent end of the said passage around the liner and this exterior chamber, and another connection between this chamber and the space for coolant in the head of the cylinder, an annular shoulder on the exterior of the liner toward its outer end, a gland-like ring passed over the outer end of the liner so that the end of this ring lies against the said annular shoulder on the liner, and studs passing through the gland r-ing into the adjacent part of the cylinder :block and serving through the ring to hold the liner in place.

HARRY RALPH RICARDO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,279,008 Ross Sept. 17, 1918 1,321,792 Jackson Nov. 11, 1919 1,816,819 Austin Aug. 4, 1931 2,146,368 Dake Feb. 7, 1939 2,244,323 Antonsen et al June 3, 1941 

